1. Field of Invention
The present invention pertains to the field of jet powered personal watercraft. More particularly, this invention is a battery powered electric jet ski having a separable hull for ease of maintenance.
2. Description of the Related Art
In the field of water sports, it is well know that personal watercraft otherwise referred to as Jet Skis are growing in popularity. In a conventional Jet Ski, a combustion engine is employed, using liquid fuel such as gasoline. For safety and convenience reasons, many Jet Ski users would rather not or cannot transport fuel to their docks or on their trailers for use in a conventional motorized Jet Ski. To this extent, gasoline can be messy and is dangerous if not used properly.
It is also well know that oil is required in combustion engines such as those used in conventional Jet Skis. Oil is used to lubricate the engine to keep it in proper working order. Like gasoline and any other petroleum product, oil is a hazardous material. Oil and gas both can be pollutants on the water in which the watercraft is operated. Petroleum products leaked into the water remain on the surface of the water in the vicinity of the watercraft. If the user or users of a Jet Ski were to fall off the watercraft or decide to swim, they will likely be in polluted water.
In view of the inconveniences and safety and environmental hazards associated with gas-powered personal watercraft, it is desirable to provide an electric personal watercraft. However, it is known that electric watercraft typically suffer from low power output and short duration of operation before power is drained.
Due to the environmental hazards associated with boats, and for various other reasons, many smaller lakes only allow electric powered boats. However, prior to the present invention, such has not been available in personal watercraft.
Conventional personal watercraft are constructed of a sealed hull typically provided with a relatively small access port for performing maintenance on the engine, pump, and other internal components. The hull is typically fabricated from upper and lower hull portions that are permanently glued and/or riveted together. The hulls of conventional personal watercraft are not intended to be separated.
A variety of personal watercraft and accessories therefor have been developed to overcome these and similar problems. Typical of the art are those devices disclosed in the following U.S. patents:
U.S. Pat. No.Inventor(s)Issue Date5,685,254G. JaquesNov. 11, 19975,806,232C. E. JamesSep. 15, 19986,073,569M. A. Motsenbarker et al.Jun. 13, 20006,273,015M. A. Motsenbarker et al.Aug. 14, 2001and the following U.S. patent applications:
U.S. patentapplication Ser. No.Inventor(s)Publication Date2001/00571474Y. Matsuda et al.Dec. 13, 20012002/0023579J. A. Profitt et al.Feb. 28, 2002
Of these patents and patent applications, the '254 device disclosed by Jacques is a hull adaptor for a personal watercraft. The hull adaptor is a second hull which is provided for the craft to be more buoyant and stable. As stated by Jacques, personal watercraft are typically configured to be powered by a small engine located toward the front of the watercraft hull. An intake channel is formed in the bottom of the hull somewhat after the engine. Jacques indicates that a major disadvantage especially for smaller watercraft is draft. Jacques continues that while the standard hull is reasonably functional for use by smaller riders, adult-sized individuals find that there is a loss of buoyancy, speed, stability and maneuverability when riding the craft. Accordingly, Jacques discloses his invention to attach to the bottom of a conventional watercraft to overcome its inherent deficiencies. Jacques does not teach a separable hull, nor an alternate means for powering a conventional personal watercraft.
The '232 device disclosed by James is a radio controlled fishing bait boat for delivering a baited fishing line to a remote location. Battery-powered electric motors for controlling a propeller and a rudder, batteries, and a controller are arranged within the interior of a hull. A pair of pivotable hatches are provided in the stern transom for access to bait storage compartments in the interior of the hull. Because of the low weight carried by the '232 device, the power plant is not of a capacity to power a human-ridden personal watercraft. Further, the small scale of the watercraft is not adaptable on a larger scale such as in a personal watercraft.
Matsuda et al., in their '474 patent application, disclose a personal watercraft of a jet-propulsive type that can maintain steering capability in a way adapted to forward movement and rearward movement of the watercraft even when throttle-close operation is performed and the amount of water ejected from a water jet pump is thereby reduced. The '474 application does not teach a means for electrically motivating a personal watercraft. Further, the '474 application does not teach a personal watercraft having a separable hull for ease of access to the internal components thereof.
The '569 and '015 patents issued to Motsenbocker et al., and the '579 application filed by Profitt et al. are each directed watercraft which take advantage of the weight of an electric motor and its component. Specifically, the '569 patent teaches “a low energy density power source that represents a large proportion (more than 10%, preferably more than 20%, more preferably greater than 30% and even more preferably greater than 50%) of the total watercraft weight . . . placed within at least one closed hull support member . . . , and a platform holding the occupants (or other cargo) are held above the support member(s) by struts.” The high weight percentage consumed by the power source is described as an “essential feature of the invention” in that it minimizes contact of the surfaces of the watercraft with wave energy. As indicated in the '015 patent, instead of overcoming the weight disadvantage of the required batteries, the inventors disclose a means to “exploit the heavy battery problem in an electric boat design that simultaneously (i) allows use of massive battery power for a small watercraft, (ii) stabilizes the watercraft, partly by decreasing its center of gravity, (iii) decreases resistance to wave action and (iv) decreases friction to boat movement.”
While the latter patent application and two issued patents discuss battery-powered watercraft, there in no teaching as to how such watercraft are operated. Further, they do not disclose a personal watercraft having a separable hull for easy access to the internal components thereof.